1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 package com.android.settings.applications;
17 
18 import android.app.AlertDialog;
19 import android.app.AppOpsManager;
20 import android.content.ActivityNotFoundException;
21 import android.content.Context;
22 import android.content.Intent;
23 import android.content.pm.ApplicationInfo;
24 import android.content.pm.PackageManager;
25 import android.os.Bundle;
26 import android.os.UserHandle;
27 import android.provider.Settings;
28 import android.support.v14.preference.SwitchPreference;
29 import android.support.v7.preference.Preference;
30 import android.support.v7.preference.Preference.OnPreferenceChangeListener;
31 import android.support.v7.preference.Preference.OnPreferenceClickListener;
32 import android.util.Log;
33 
34 import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
35 import com.android.settings.R;
36 import com.android.settings.applications.AppStateAppOpsBridge.PermissionState;
37 import com.android.settings.applications.AppStateWriteSettingsBridge.WriteSettingsState;
38 import com.android.settings.overlay.FeatureFactory;
39 import com.android.settingslib.applications.ApplicationsState.AppEntry;
40 
41 import java.util.List;
42 
43 public class WriteSettingsDetails extends AppInfoWithHeader implements OnPreferenceChangeListener,
44         OnPreferenceClickListener {
45 
46     private static final String KEY_APP_OPS_PREFERENCE_SCREEN = "app_ops_preference_screen";
47     private static final String KEY_APP_OPS_SETTINGS_SWITCH = "app_ops_settings_switch";
48     private static final String KEY_APP_OPS_SETTINGS_PREFS = "app_ops_settings_preference";
49     private static final String KEY_APP_OPS_SETTINGS_DESC = "app_ops_settings_description";
50     private static final String LOG_TAG = "WriteSettingsDetails";
51 
52     private static final int [] APP_OPS_OP_CODE = {
53             AppOpsManager.OP_WRITE_SETTINGS
54     };
55 
56     // Use a bridge to get the overlay details but don't initialize it to connect with all state.
57     // TODO: Break out this functionality into its own class.
58     private AppStateWriteSettingsBridge mAppBridge;
59     private AppOpsManager mAppOpsManager;
60     private SwitchPreference mSwitchPref;
61     private Preference mWriteSettingsPrefs;
62     private Preference mWriteSettingsDesc;
63     private Intent mSettingsIntent;
64     private WriteSettingsState mWriteSettingsState;
65 
66     @Override
onCreate(Bundle savedInstanceState)67     public void onCreate(Bundle savedInstanceState) {
68         super.onCreate(savedInstanceState);
69 
70         Context context = getActivity();
71         mAppBridge = new AppStateWriteSettingsBridge(context, mState, null);
72         mAppOpsManager = (AppOpsManager) context.getSystemService(Context.APP_OPS_SERVICE);
73 
74         addPreferencesFromResource(R.xml.app_ops_permissions_details);
75         mSwitchPref = (SwitchPreference) findPreference(KEY_APP_OPS_SETTINGS_SWITCH);
76         mWriteSettingsPrefs = findPreference(KEY_APP_OPS_SETTINGS_PREFS);
77         mWriteSettingsDesc = findPreference(KEY_APP_OPS_SETTINGS_DESC);
78 
79         getPreferenceScreen().setTitle(R.string.write_settings);
80         mSwitchPref.setTitle(R.string.permit_write_settings);
81         mWriteSettingsPrefs.setTitle(R.string.write_settings_preference);
82         mWriteSettingsDesc.setSummary(R.string.write_settings_description);
83 
84         mSwitchPref.setOnPreferenceChangeListener(this);
85         mWriteSettingsPrefs.setOnPreferenceClickListener(this);
86 
87         mSettingsIntent = new Intent(Intent.ACTION_MAIN)
88                 .addCategory(Settings.INTENT_CATEGORY_USAGE_ACCESS_CONFIG)
89                 .setPackage(mPackageName);
90     }
91 
92     @Override
onPreferenceClick(Preference preference)93     public boolean onPreferenceClick(Preference preference) {
94         if (preference == mWriteSettingsPrefs) {
95             if (mSettingsIntent != null) {
96                 try {
97                     getActivity().startActivityAsUser(mSettingsIntent, new UserHandle(mUserId));
98                 } catch (ActivityNotFoundException e) {
99                     Log.w(LOG_TAG, "Unable to launch write system settings " + mSettingsIntent, e);
100                 }
101             }
102             return true;
103         }
104         return false;
105     }
106 
107     @Override
onPreferenceChange(Preference preference, Object newValue)108     public boolean onPreferenceChange(Preference preference, Object newValue) {
109         if (preference == mSwitchPref) {
110             if (mWriteSettingsState != null && (Boolean) newValue != mWriteSettingsState
111                     .isPermissible()) {
112                 setCanWriteSettings(!mWriteSettingsState.isPermissible());
113                 refreshUi();
114             }
115             return true;
116         }
117         return false;
118     }
119 
setCanWriteSettings(boolean newState)120     private void setCanWriteSettings(boolean newState) {
121         logSpecialPermissionChange(newState, mPackageName);
122         mAppOpsManager.setMode(AppOpsManager.OP_WRITE_SETTINGS,
123                 mPackageInfo.applicationInfo.uid, mPackageName, newState
124                 ? AppOpsManager.MODE_ALLOWED : AppOpsManager.MODE_ERRORED);
125     }
126 
logSpecialPermissionChange(boolean newState, String packageName)127     void logSpecialPermissionChange(boolean newState, String packageName) {
128         int logCategory = newState ? MetricsEvent.APP_SPECIAL_PERMISSION_SETTINGS_CHANGE_ALLOW
129                 : MetricsEvent.APP_SPECIAL_PERMISSION_SETTINGS_CHANGE_DENY;
130         FeatureFactory.getFactory(getContext()).getMetricsFeatureProvider().action(getContext(),
131                 logCategory, packageName);
132     }
133 
canWriteSettings(String pkgName)134     private boolean canWriteSettings(String pkgName) {
135         int result = mAppOpsManager.noteOpNoThrow(AppOpsManager.OP_WRITE_SETTINGS,
136                 mPackageInfo.applicationInfo.uid, pkgName);
137         if (result == AppOpsManager.MODE_ALLOWED) {
138             return true;
139         }
140 
141         return false;
142     }
143 
144     @Override
refreshUi()145     protected boolean refreshUi() {
146         mWriteSettingsState = mAppBridge.getWriteSettingsInfo(mPackageName,
147                 mPackageInfo.applicationInfo.uid);
148 
149         boolean canWrite = mWriteSettingsState.isPermissible();
150         mSwitchPref.setChecked(canWrite);
151         // you can't ask a user for a permission you didn't even declare!
152         mSwitchPref.setEnabled(mWriteSettingsState.permissionDeclared);
153         mWriteSettingsPrefs.setEnabled(canWrite);
154         if (getPreferenceScreen().findPreference(KEY_APP_OPS_SETTINGS_PREFS) != null) {
155             getPreferenceScreen().removePreference(mWriteSettingsPrefs);
156         }
157         return true;
158     }
159 
160     @Override
createDialog(int id, int errorCode)161     protected AlertDialog createDialog(int id, int errorCode) {
162         return null;
163     }
164 
165     @Override
getMetricsCategory()166     public int getMetricsCategory() {
167         return MetricsEvent.SYSTEM_ALERT_WINDOW_APPS;
168     }
169 
getSummary(Context context, AppEntry entry)170     public static CharSequence getSummary(Context context, AppEntry entry) {
171         WriteSettingsState state;
172         if (entry.extraInfo instanceof WriteSettingsState) {
173             state = (WriteSettingsState) entry.extraInfo;
174         } else if (entry.extraInfo instanceof PermissionState) {
175             state = new WriteSettingsState((PermissionState) entry.extraInfo);
176         } else {
177             state = new AppStateWriteSettingsBridge(context, null, null).getWriteSettingsInfo(
178                     entry.info.packageName, entry.info.uid);
179         }
180 
181         return getSummary(context, state);
182     }
183 
getSummary(Context context, WriteSettingsState writeSettingsState)184     public static CharSequence getSummary(Context context, WriteSettingsState writeSettingsState) {
185         return context.getString(writeSettingsState.isPermissible() ? R.string.write_settings_on :
186                 R.string.write_settings_off);
187     }
188 
getSummary(Context context, String pkg)189     public static CharSequence getSummary(Context context, String pkg) {
190         // first check if pkg is a system pkg
191         boolean isSystem = false;
192         PackageManager packageManager = context.getPackageManager();
193         try {
194             ApplicationInfo appInfo = packageManager.getApplicationInfo(pkg, 0);
195             if ((appInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 0) {
196                 isSystem = true;
197             }
198         } catch (PackageManager.NameNotFoundException e) {
199             // pkg doesn't even exist?
200             Log.w(LOG_TAG, "Package " + pkg + " not found", e);
201             return context.getString(R.string.write_settings_off);
202         }
203 
204         AppOpsManager appOpsManager = (AppOpsManager) context.getSystemService(Context
205                 .APP_OPS_SERVICE);
206         List<AppOpsManager.PackageOps> packageOps = appOpsManager.getPackagesForOps(
207                 APP_OPS_OP_CODE);
208         if (packageOps == null) {
209             return context.getString(R.string.write_settings_off);
210         }
211 
212         int uid = isSystem ? 0 : -1;
213         for (AppOpsManager.PackageOps packageOp : packageOps) {
214             if (pkg.equals(packageOp.getPackageName())) {
215                 uid = packageOp.getUid();
216                 break;
217             }
218         }
219 
220         if (uid == -1) {
221             return context.getString(R.string.write_settings_off);
222         }
223 
224         int mode = appOpsManager.noteOpNoThrow(AppOpsManager.OP_WRITE_SETTINGS, uid, pkg);
225         return context.getString((mode == AppOpsManager.MODE_ALLOWED) ?
226                 R.string.write_settings_on : R.string.write_settings_off);
227     }
228 }
229